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BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Goodwill and Indefinite-Lived Intangible Asset Impairments (Details) | 12 Months Ended
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Sep. 30, 2025 USD ($) reportingUnit | Sep. 30, 2024 USD ($) reportingUnit | Sep. 30, 2023 USD ($) reportingUnit
Organization, Consolidation and Presentation of Financial Statements [Abstract] |  |  |
Number of reporting units | reportingUnit | 6 | 6 | 6
Goodwill impairment | $ 18,885,000 | $ 0 | $ 1,721,000
Goodwill Impairment Loss Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed Flag |  |  | goodwill impairment
Impairment indefinite-lived asset | $ 0 | $ 0 | $ 0

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